Live updates: Government shutdown, as it happens

The U.S. government is shut down for the first time in nearly two decades, as the House and Senate ran out of time and options to keep it open. The Democratic Senate on Monday twice rejected GOP demands to delay key portions of what has become to known as Obamacare as a condition for keeping the government open.

An estimated 800,000 federal workers faced furloughs though many were told work a half day Tuesday. Critical functions like air traffic control and military operations will continue. Social Security benefits will be paid. National parks and most federal offices will close.

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